When Vint Cerf, widely regarded as the “father of the Internet,” helped write the first software code that would begin to lay the foundation for the worldwide Web in 1973, the technology was designed to provide connections for about four billion computers, each with its own unique digital address.

Unfortunately, thanks to the proliferation of PCs, smartphones and Web-connected video game consoles, four billion addresses simply isn’t enough.

On Wednesday of next week, the last of those addresses will be gobbled up, and the Web as we know it will enter a new era of connectivity that promises to change the way we think about the Internet.

For his part, Mr. Cerf — he now serves as chief technology evangelist for Google Inc. — said the decision to limit the number of Web addresses was his “fault.”

“Who the hell knew how much address space we needed?” Mr. Cerf was quoted as saying in an interview last week.

The Web addresses most users will be familiar with are the alphanumeric domain names that end in with a .com, .ca or .edu, but what many users don’t realize is that every device connected to the Internet has its own unique Internet protocol, or IP, address.

An IP address is a unique digital identifier for a connected device, kind of like a phone number; just as it’s impossible to make a call without a phone number, without an IP address, a computer can’t connect to the Internet.

The current version of IP addresses most commonly used on the Internet is known as the Internet protocol version 4 (IPv4) standard, of which there are about 4.3 billion unique addresses, and rapidly disappearing.

As of Wednesday, there were an estimated 11 million unassigned IPv4 addresses remaining in the global pool. However, regional authorities are still allocating the last of their addresses. The solution is known as Internet protocol version 6 — IPv6.

Unlike IPv4 addresses, which consist of four numbers separated by dots, IPv6 addresses have 16 numbers with dots in between, which exponentially increases the number of available addresses.

How many addresses does IPv6 offer? About 340 undecillion (a number featuring 36 zeroes) or roughly enough addresses to give every atom on planet Earth its own unique IP address.

“The Internet was invented with the idea that nobody would need more than four billion IP addresses,” said Michael Hyatt, chief executive of BlueCat Networks, a Toronto-based technology firm that specializes in helping companies manage all the IP addresses needed to run their businesses.

“It was kind of akin to Bill Gates asking who would ever need more than 64 K of [memory] in a computer? It’s not that the Internet is getting bigger, it’s that what people are doing with the Internet is changing and that the Internet is becoming incredibly pervasive.

“The bottom line is that everything that we’re developing today is becoming IP-enabled.”

About 140,000 corporations around the world, including titans Microsoft Corp., Google Inc. and Hewlett-Packard Co. have already been granted what is known as a “Slash 32,” which is essentially a block of four billion IPv6 networks. Each network within a Slash 32 contains trillions of unique addresses.

Of course, with companies now faced with the prospect of tracking and managing an exponential number of even longer addresses, it’s no longer possible to organize all those IP addresses using something like a spreadsheet.

That’s where companies like BlueCat come in. The company’s technology is used by companies to track and manage the IP addresses it assigns to devices inside its IT infrastructure.

BlueCat is also helping companies manage the transition from IPv4 to IPv6, a process that could take many years to complete.

“BlueCat is the unintended consequence of IP proliferation,” Mr. Hyatt said. “We think people are going to use a combination of IPv4 and IPv6 for perhaps a decade. But the thing is, you’re going to be able to do both and do both at a high level management layer. When our product is in an enterprise, it allows you to command and control all that information from one centralized access point.”

Using current IPv4 technology, when a user visits a website it’s a one way conversation. There’s no direct connection between the user and the site, since the connection is facilitated by an intermediary, sometimes referred to as a network address translation (NAT).

According to Joel Conover, senior manager of borderless networks architecture for Cisco Systems Inc., with current IPv4 and NAT technology in place, it’s a bit like trying to get someone to call you back when you have your called ID blocked.

“That’s the way the Web works today; you sit behind a firewall with a NAT in it, you call out and once you’ve called out, the person on the other end knows what your phone number is and where you are, so they can talk back to you,” he said.

“But if they call you and you have your caller ID blocked, they could never reach you. A NAT is like blocking your caller ID. This is the problem that IPv6 solves. It gives every device, every person, every entity its own unique number that is always reachable.”

Where IPv6 technology gets really interesting is when technologists start to think about things like radio-frequency identification tags and microscopic robots, or nanotechnology.

“Imagine if nanotechnology becomes affordable to the point where you could create a nanotech of some sort — something in your bloodstream or something that you wear,” said Mr. Conover.

“Now imagine you could produce that for the cost of an M&M … you could be talking about having thousands, or millions of these things in every human being. It’s futurist stuff. It would require a quantum change in the way we think about technology. But is it out of the question? No. The people that are building out IPv6 are looking at the bigger picture, so that we don’t have to be looking at another changeover in 20 years.”

On June 6, several of the world’s largest Web companies, including Facebook, Google and Yahoo Inc., will participate in “World IPv6 Day,” and switch their services over to the IPv6 standard for 24 hours, in an effort to “kick the tires” on the technology and iron out any bugs that may arise from the changeover.

If everything goes according to plan, most Web users won’t be aware that a change has actually occurred as the Internet begins to make the transition to IPv6. What will change for them are the kinds of new experiences they can expect as companies take advantage of the advantages of a wealth of new IP addresses.